2D Drawing & Photo Software
Corel PaintShopProPhoto X2
I have chosen to review these 2D software packages, because I own them and they cover the range of abilities and costs that you would expect from amateur to hobbyist to professional status.
Okay, as a student or other financially handicapped individual The GIMP is the best place to start as it is totally free and is said to be customisable to echo PhotoShop - we'll see.
Corel's PaintShop Pro Photo
Corel's PaintShop Pro Photo, recently bought by Corel from Jasc software, is an impressive piece of software at a very reasonable price - in fact when I bought it - a year or so ago - I got it in a package deal with Ulead Video Studio at less than the then price of PaintShop alone. It - like PhotoShop - has an automatic tiling feature, various filters including red-eye removal, backlighting, fill flash and depth of field. It also has the normal functions like brightness and contrast, levels, negative, hue and saturation, noise, blur etc etc, plus something called Picture Tubes, which I don't think PhotoShop can quite emulate, the closest that gets is being able to save and create your own brushes, so it would probably be possible.
One thing I have found to be much easier in PaintShop than in PhotoShop is the ease with which you can save an image - either from the web or from an open image in PaintShop - you just use Ctrl+Shift+V. This was easier in Paintshop Pro 7 and 8 - it was just Ctrl+V - in PhotoX2 that is now to paste into a new layer in the current open and active image. (as it was in PhotoX1, too)
This particular action is miles harder in PhotoShop as you first need to create a new empty image - of either the correct size or larger - which is a heck of a palaver even if it's your own image on your own hard drive... When I had a total hard drive melt-down a while back, and some of my images were only still existing on my website, I had a heck of a job to save them from the web - or would have done if I only had PhotoShop, and not PaintShop too.
Adobe PhotoShop CS4
PhotoShop CS4 has problems that CS 2 did not have, it's all to do with the new Open GL Drawing facility. On my machine - which unfortunately is running Windows XP Media Centre (my fault: I thought it was a step up from XP Professional, and not as it turns out a step backwards.) and Adobe has said that they do not support Media Centre - this new open GL facility seldom works. However, the last time I had an open GL problem it was solved by an update to the NVIDIA drivers, and as a new update for it came out in April this year, as soon as all my rendering is over I will be updating that - it may help.
The PhotoShop Seamless Tiling filter is much better than the same feature in PaintShop, in that is more controlable by the artist, although with some practice a similar job can be accomplished in PaintShop, it is easier in PhotoShop, or I find it so.
The single big difference seems to be a fancy feature called 3D, which is fun to use and could be useful in creating titles, or simple banners. I will have to search for a tutorial on this to see just how flexible it can be.